Proton Magnetic Resonance Spectroscopy. Configurational Stability of Neohexyl(3,3-dimethylbutyl) Organometallic Compounds
- Creators
- Witanowski, Michal
- Roberts, John D.
Abstract
The proton resonance spectra of dilute ether solutions of neohexyl(3,3-dimethylbutyl) organometallic compounds have been investigated as a function of temperature as a means of determining their configurational stabilities. Neohexyllithium, dineohexylmagnesium (free from magnesium chloride), and dineohexylzinc appear to undergo the inversion of configuration at the a-methylene groups at various temperatures. The activation energies for inversion are approximately 15, 20, and 26 kcal. for the lithium, magnesium, and zinc compounds, respectively. Inversion appears to be a first-order process for the lithium and magnesium compounds. This fact and the general dependence of the inversion rate on the nature of the metal suggest a dissociation-recombination mechanism (SE1). Trineohexylaluminum and dineohexylmercury were found to be configurationally stable up to 150-160º. The chemical shifts of the CH_2-CH_2 groupings in these organometallic compounds can be correlated with the electronegativity of the metal atoms.
Additional Information
© 1966 American Chemical Society. Received September 27, 1965. Supported in part by the National Science Foundation and the Office of Naval Research.Additional details
- Eprint ID
- 61124
- Resolver ID
- CaltechAUTHORS:20151014-144944013
- NSF
- Office of Naval Research (ONR)
- Created
-
2015-10-14Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field
- Other Numbering System Name
- Caltech Gates and Crellin Laboratories of Chemistry
- Other Numbering System Identifier
- 3251